Replace SARSingleNode with SAR

[simonzhaoms]

Description

This PR replaces all SARSingleNode with SAR, because SARSingleNode has been already imported as SAR in __init__.py:
https://github.com/microsoft/recommenders/blob/aeb6b0b12e177b3eaf55bb7ab2b747549a541394/recommenders/models/sar/__init__.py#L4

Related Issues

Checklist:

• I have followed the contribution guidelines and code style for this project.
• I have added tests covering my contributions.
• I have updated the documentation accordingly.
• This PR is being made to staging branch and not to main branch.

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[miguelgfierro]

Agree.

Also, you migth want to delete this guy https://github.com/microsoft/recommenders/blob/main/recommenders/models/sar/__init__.py#L4

[miguelgfierro]

oh, I understood this wrong :-) I thought you were going to eliminate the name SAR single node and put SAR everywhere.

Do you want to leave it with sar single node or you want to leave everything as SAR?

[simonzhaoms]

oh, I understood this wrong :-) I thought you were going to eliminate the name SAR single node and put SAR everywhere.

Do you want to leave it with sar single node or you want to leave everything as SAR?

@miguelgfierro In recommenders/models/sar/__init__.py, SARSingleNode is renamed as SAR, so I think all occurrences of SARSingleNode should be replaced with SAR. Otherwise, from .sar_singlenode import SARSingleNode as SAR is useless, isn't it?

[miguelgfierro]

Otherwise, from .sar_singlenode import SARSingleNode as SAR is useless, isn't it?

yes exactly, what I meant is that I thought you were planning to change all instances of SARSingleNode to SAR